Bukkit

configuration:
    enabled: true
    recipes:
          diamond-enabled: false
          emerald-enabled: false
          redstone-enabled: false
          gold-enabled: true
          iron-enabled: true
          coal-enabled: true
          lapis-enabled: false
          quartz-enabled: false
          chainmail-enabled: true
          rotten_flesh-enabled: true
          cobweb-enabled: true
          string-enabled: true
          saddle-enabled: true
          grass-enabled: true
          mossycobble-enabled: true
          crackedbrick-enabled: true
          mossybrick-enabled: true
          circlebrick-enabled: true
          command-enabled: false
          redstone_dust-enabled: true
          spawner-enabled: false

This above is the optimal setting for a survival server.

Explanation

Smelting config part

diamond-enabled >> should be smelting diamonds to diamond ore be available?
emerald-enabled >> should be smelting emerald to emerald ore be available?
redstone-enabled >> should be smelting redstone to redstone ore be available?
gold-enabled >> should be smelting gold to gold ore be available?
iron-enabled >> should be smelting iron to iron ore be available?
coal-enabled >> should be smelting coal to coal ore be available?
lapis-enabled >> should be smelting lapis to lapis ore be available?
quartz-enabled >> should be smelting quartz to quartz ore be available?

Crafting config part

rotten_flash-enabled >> should leather be craftable through 4 rotten flash?
chainmail-enabled >> should the chainmail recipes be available?
cobweb-enabled >> should the cobweb recipes be available?
string-enabled >> should the string recipes be available?
saddle-enabled >> should the saddle recipes be available?
grass-enabled >> should the grass block recipes be available?
mossycobble-enabled >> should the mossy cobblestone recipe be available?
crackedbrick-enabled >> should the cracked brick recipes be available?
mossybrick-enabled >> should the mossy brick recipes be available?
circlebrick-enabled >> should the circle brick recipes be available?
command-enabled >> should the command block recipes be available?
redstone_dust-enabled >> should the redstone dust recipe be available?
spawner-enabled >> should spawner crafting be enabled?

Notes

- true means enabled and false means disabled!
- All crafting configs are named like: *product*-enabled, except the rotten_flesh config because the product there is leather.
- All smelting configs are named like: *input*-enabled.
- spawner-enabled won't enable spawner at all at the moment. It is still a WIP feature.